Kmu Mdcat 2023 Retake — Solved Past Paper with Answers

Q1. Cell death due to tissue damage is called:

• A. Necrosis✓
• B. Metastasis
• C. Apoptosis
• D. Epistasis

Explanation: [A] Necrosis is the death of a body tissue,occurring when too little blood flows to the tissue.[B]Metastasis means that cancer has spread to different parts of body[C] Apoptosis the process of programmed cell death[D] Epistasis is a circumstance where the expression of one gene is modified by expression of one or more gene

Q2. Autoclave chambers are used for _ of surgical instruments?

• A. Sterlization✓
• B. Filtration
• C. Desiccation
• D. Radiation

Explanation: Autoclave chambers, also known as autoclaves or steam sterilizers, are used to sterilize surgical instruments and other medical equipment by exposing them to high-pressure steam at a temperature of around 121°C (250°F) for a specified period. This process kills all forms of microbial life, including bacteria, viruses, and spores, making the instruments safe for use in surgical procedures.

Q3. The incubation period of Syphilis is:

• A. 1-2 weeks
• B. 2-3 weeks✓
• C. 3-4 weeks
• D. 7 days

Explanation: The incubation period of syphilis, which is the time between exposure to the bacteria (Treponema pallidum) and the appearance of symptoms, typically ranges from 2 to 3 weeks. However, it can vary from 10 to 90 days, with an average of around 21 days.

Q4. Muscle fatigue results due to deficiency of _ and excess accumulation of _.

• A. Adenosine triphosphate, Lactic acid✓
• B. Adenosine triphosphate, Ionic imbalance
• C. Glucose, Lactic acid
• D. Glucose, Ionic imbalance

Explanation: Muscle fatigue occurs when muscles are unable to generate force or contract due to a combination of factors. The two main factors are: 1. Deficiency of Adenosine Triphosphate (ATP): ATP is the primary energy source for muscle contractions. When ATP levels are depleted, muscles cannot contract effectively, leading to fatigue. 2. Excess accumulation of Lactic Acid: During intense muscle activity, anaerobic metabolism occurs, leading to the accumulation of lactic acid. High levels of lactic acid disrupt muscle function, leading to fatigue, soreness, and stiffness.

Q5. A male or female child of an affected mother has 50% chance of acquiring the disorder. Such a disorder is:

• A. X linked recessive disorder
• B. X linked dominant disorder✓
• C. Y linked dominant disorder
• D. Y linked recessive disorder

Explanation: An X-linked dominant disorder is a genetic condition that is caused by a mutation in a gene located on the X chromosome. Since females have two X chromosomes, they have two copies of the gene, while males have only one X chromosome and one copy of the gene.In the case of an X-linked dominant disorder:- A female with the mutated gene (Xm) has a 50% chance of passing it to each of her children (both sons and daughters).- A male with the mutated gene (Xm) will pass it to all of his daughters (who will be carriers) but none of his sons (who will not inherit the X chromosome).The 50% chance of acquiring the disorder mentioned in the question is consistent with an X-linked dominant disorder.

Q6. Which is the factory for synthesis of sugars in autotrophic eukaryotes?

• A. Mitochondria
• B. Ribosome
• C. Chloroplast✓
• D. Amyloplast

Explanation: Chloroplasts are organelles found in autotrophic eukaryotes, such as plants and algae, where photosynthesis takes place. They are responsible for converting light energy into chemical energy, producing glucose and oxygen from carbon dioxide and water. Chloroplasts are often referred to as the "factory" for sugar synthesis in autotrophic eukaryotes.

Q7. The co-enzyme NAD is made up of?

• A. Vitamins
• B. Amino acids
• C. Nucleotides✓
• D. Sugar

Explanation: NAD (Nicotinamide adenine dinucleotide) is a coenzyme that plays a central role in various cellular processes, including energy metabolism, DNA repair, and cellular signalling. It is composed of two nucleotides:1. Adenine nucleotide (derived from vitamin B3, Niacin)2. Nicotinamide nucleotide (derived from vitamin B3, Niacin)NAD is formed by the condensation of these two nucleotides, making it a dinucleotide.

Q8. Storage diseases are caused by the excessive accumulation of substances within the cell, due to defects(mutations) in one of the _ enzymes.

• A. Amylase
• B. Lysosomal✓
• C. Lyase
• D. Lipase

Explanation: Storage diseases, also known as lysosomal storage diseases, are a group of genetic disorders caused by defects (mutations) in lysosomal enzymes. Lysosomes are membrane-bound organelles responsible for cellular digestion and recycling. They contain various enzymes that break down and degrade cellular waste, toxins, and excess substances.When lysosomal enzymes are defective or deficient, the substances they normally break down accumulate within the cell, leading to cellular dysfunction and disease. Examples of lysosomal storage diseases include:- Tay-Sachs disease- Gaucher's disease- Pompe disease- Fabry disease

Q9. The function of the nucleolus is to form:

• A. Nuclear envelope
• B. Chromosome
• C. rRNA✓
• D. Cytoplasm

Explanation: The nucleolus is a region within the nucleus of eukaryotic cells where ribosome synthesis occurs. Its primary function is to transcribe and assemble the ribosomal RNA (rRNA) molecules, which are essential components of ribosomes. Ribosomes are responsible for protein synthesis in cells.The nucleolus performs the following functions:1. rRNA transcription: Transcribes the rRNA genes into rRNA molecules.2. rRNA processing: Processes the transcribed rRNA molecules into mature rRNA.3. Ribosome assembly: Assembles the rRNA molecules with proteins to form complete ribosomes.

Q10. A shallow groove in cerebrum is called _ and deep groove is called _.

• A. Sulcus, Fissure✓
• B. Fissure, Sulcus
• C. Gyrus, Fissure
• D. Fissure, Gyrus

Explanation: In the cerebrum, the outer layer of the brain, there are folds and grooves that increase the surface area. These folds and grooves are classified into two types based on their depth: 1. Sulcus (plural: sulci): A shallow groove or furrow in the cerebrum. Sulci are typically 1-2 cm deep and separate adjacent gyri (folds). 2. Fissure: A deep groove or cleft in the cerebrum. Fissures are typically 2-5 cm deep and separate larger regions of the brain, such as the hemispheres.

Q11. What brings the membrane potential to threshold?

• A. Influx of sodium ions across the postsynaptic membrane✓
• B. Outflow of sodium ions across the postsynaptic membrane
• C. Outflow of calcium ions across the postsynaptic membrane
• D. Influx of potassium ions across the postsynaptic membrane

Explanation: When an excitatory neurotransmitter binds to its receptor on the postsynaptic neuron, it triggers an influx of sodium ions (Na+) across the postsynaptic membrane. This influx of positively charged ions depolarizes the membrane, bringing the membrane potential closer to threshold. If the membrane potential reaches threshold (typically around -55mV), an action potential is generated.

Q12. What alters the shape of enzymes and makes them functional.

• A. Cofactors✓
• B. Other enzymes
• C. Proteins
• D. Both a and c

Explanation: Cofactors are non-protein chemical compounds or metallic ions that bind to an enzyme and are essential for the enzyme's activity. They help stabilize the enzyme structure or participate in the enzyme's catalytic function, thereby altering the enzyme's shape to make it functional.

Q13. Which of the following is known as the vessels of the vessels?

• A. Vasa vasorum✓
• B. Tunica media
• C. Tunica externa
• D. Tunica interna

Explanation: Vasa vasorum is a network of small blood vessels that supply oxygen and nutrients to the walls of larger blood vessels, such as arteries and veins. The term "vasa vasorum" literally means "vessels of the vessels" in Latin, as they provide nourishment to the vessels themselves.

Q14. Which of the following is true about the occurrence of erythroblastosis foetalis?

• A. Occurs when both father and mother are Rh +ive
• B. Occurs when both father and mother are Rh -ive
• C. Occurs when mother is Rh+ive and father is Rh -ive
• D. Occurs when mother is Rh-ive and father is Rh +ive✓

Explanation: Erythroblastosis fetalis (EF) is a condition that occurs when there is an incompatibility between the blood types of a mother and her fetus. Specifically, it occurs when:- The mother is Rh-negative (Rh-)- The father is Rh-positive (Rh+)- The fetus inherits the Rh+ antigen from the fatherDuring pregnancy, the mother's immune system may recognize the Rh+ antigen on the fetus's red blood cells as foreign and produce antibodies against it. These antibodies can then cross the placenta and attack the fetus's red blood cells, leading to hemolysis (breakdown of red blood cells) and potentially severe anemia in the fetus.

Q15. All are properties of water except:

• A. Universal solvent
• B. Polar nature
• C. Hydrogen bonding
• D. Becomes denser when it freezes.✓

Explanation: The statement in option (d) is false and not a property of water. Water actually becomes less dense when it freezes. This occurs because the hydrogen bonds between water molecules form a crystalline structure in ice that is less compact than in liquid water, causing ice to float.

Q16. Thymus gland is involved in maturation of which of the following?

• A. Platelets
• B. Eosinophils
• C. B-Lymphocytes
• D. T-Lymphocytes✓

Explanation: The thymus gland is a primary lymphoid organ responsible for the maturation and development of T-lymphocytes (T cells). T cells are a type of white blood cell that plays a central role in cell-mediated immunity.The thymus gland:1. Selects and matures T cells from immature precursors2. Educates T cells to recognize self and non-self antigens3. Eliminates autoreactive T cells to prevent autoimmune diseases

Q17. Which component is present only in the cell wall of Gram-positive bacteria but NOT in Gram-negative bacteria?

• A. Teichoic acids✓
• B. Lipids
• C. Peptidoglycan
• D. Periplasmic space

Explanation: Teichoic acids are unique components found only in the cell walls of Gram-positive bacteria. They are acidic, phosphate-containing polysaccharides that play a crucial role in maintaining the structural integrity of the cell wall and providing a negative charge to the cell surface.Gram-positive bacteria have a thick peptidoglycan layer (20-80 nanometers) and a teichoic acid layer, whereas Gram-negative bacteria have a thinner peptidoglycan layer (2-3 nanometers) and an outer membrane containing lipopolysaccharides.

Q18. In breastfeeding mothers, which hormone would be at an increased level?

• A. Prolactin✓
• B. Thyroxin
• C. Aldosterone
• D. Insulin

Explanation: Prolactin is a hormone produced by the pituitary gland that plays a crucial role in lactation and breastfeeding. During pregnancy and breastfeeding, prolactin levels increase significantly, stimulating the growth of milk-producing cells in the breast and initiating milk production. In breastfeeding mothers, prolactin levels remain elevated to maintain milk production and support lactation. Frequent suckling by the baby stimulates the release of prolactin, ensuring a continuous supply of milk.

Q19. Mendel's law of independent assortment can be explained by:

• A. Behaviour of chromosomes in mitosis
• B. Behaviour of chromosomes in meiosis✓
• C. Gene behaviour in mitosis
• D. Both a and b

Explanation: Mendel's law of independent assortment states that different genes are sorted independently of each other during gamete formation. This means that the alleles of one gene do not influence the alleles of another gene.This law can be explained by the behavior of chromosomes during meiosis, specifically:1. Chromosomes pair up and exchange genetic material during crossing over2. Homologous chromosomes separate and move to opposite poles during anaphase I3. Sister chromatids separate and move to opposite poles during anaphase IIThis results in a random combination of chromosomes and genes in the gametes, ensuring independent assortment.

Q20. Which of the following is a rod shape virus?

• A. Bacteriophage
• B. Herpes virus
• C. Hepatitis virus
• D. Tobacco mosaic virus✓

Explanation: Tobacco mosaic virus (TMV) is a rod-shaped virus that infects plants, particularly tobacco and other solanaceous species. It has a helical structure, with a protein coat and a single-stranded RNA genome.

Q21. Glucose is classified as a _:

• A. Monosaccharides✓
• B. Disaccharides
• C. Oligosaccharides
• D. Polysaccharides

Explanation: Glucose is a simple sugar, also known as a monosaccharide, which means it cannot be broken down into simpler sugars. Monosaccharides are the building blocks of carbohydrates and have the general formula (CH2O)n.

Q22. Which of the following is the opposite of condensation reaction?

• A. Decarboxylation
• B. Hydration
• C. Dehydration
• D. Hydrolysis✓

Explanation: Condensation reactions involve the combination of two molecules to form a new molecule, often with the loss of a small molecule like water or methanol. Hydrolysis, on the other hand, is the reverse process, where a molecule is split into two or more smaller molecules using water.

Q23. The cells of the non virulent strain of Streptococcus pneumonia are:

• A. Capsulated and S-Type
• B. Non-capsulated and S-Type
• C. Capsulated and R-Type
• D. Non-capsulated and R-Type✓

Explanation: Streptococcus pneumoniae strains are classified into two main types based on their capsule:- S-type (Smooth-type): Capsulated, virulent strains with a smooth colony morphology.- R-type (Rough-type): Non-capsulated, non-virulent strains with a rough colony morphology.The capsule is a layer of polysaccharides surrounding the bacterial cell wall, which helps protect the bacteria from phagocytosis and is a key virulence factor. Non-virulent strains lack this capsule, making them more susceptible to host immune responses.

Q24. The total number of cranial nerves in the human body is.

• A. 12 pairs✓
• B. 24 pairs
• C. 31 pairs
• D. 62 pairs

Explanation: There are 12 pairs of cranial nerves in the human body, which emerge from the brain and brainstem. These nerves are responsible for controlling various functions such as sensory perception, movement, and autonomic functions like heart rate and digestion.

Q25. Enzymes are...

• A. Carbohydrates
• B. Proteins✓
• C. Lipids
• D. Can be lipid or proteins

Explanation: Enzymes are biological molecules that catalyze chemical reactions in living organisms. The majority of enzymes are proteins, which are complex biomolecules composed of amino acids. Protein enzymes have specific shapes and active sites that allow them to bind to substrates and facilitate chemical reactions.

Q26. Who proposed the concept that an organism can pass on acquired modifications to its offspring?

• A. Lamarck✓
• B. Darwin
• C. Malthus
• D. Aristotle

Explanation: Jean-Baptiste Lamarck (1744-1829) proposed the theory of inheritance of acquired characteristics, also known as Lamarckism. He suggested that organisms can pass on traits they acquire during their lifetime to their offspring. For example, he believed that giraffes developed long necks because they stretched to reach leaves, and then passed this trait to their offspring.However, this theory was later disputed and largely discredited by the scientific community, particularly after the discovery of genetics and the modern synthesis of evolution.

Q27. Cytotoxic T-Cells _

• A. Directly kill invaders✓
• B. Aid B cells in their job
• C. Both a and b
• D. Suppress T cell activity

Explanation: Cytotoxic T-cells (also known as CD8+ T-cells) are a type of immune cell that directly kill infected cells, cancer cells, or cells that have been damaged in other ways. They recognize and bind to antigens presented by infected or abnormal cells and release toxic substances, such as perforin and granzymes, that lead to the destruction of the targeted cells.

Q28. A bacterium with single polar flagellum is:

• A. Amphitrichous
• B. Atrichous
• C. Lophotrichous
• D. Monotrichous✓

Explanation: A bacterium with a single polar flagellum is classified as Monotrichous. This means that the flagellum is located at one end (pole) of the bacterial cell.

Q29. The genome of the Human Immunodeficiency Virus (HIV) is made up of:

• A. cDNA
• B. DNA
• C. RNA✓
• D. rRNA

Explanation: HIV is a retrovirus with a genome made of two single-stranded RNA molecules, about 9,700 nucleotides long. It carries genes that code for its essential proteins. After entering a host cell, its RNA is converted into DNA by reverse transcriptase and then integrated into the host genome so the virus can replicate.

Q30. Hip joint and shoulder joint are examples of:

• A. Cartilaginous joints
• B. Synovial joint
• C. Hinge joint
• D. Ball and socket joint✓

Explanation: Hip and shoulder joints are examples of ball and socket joints, while ball and socket joints and hinge joints are examples of synovial joints.

Q31. Locus of a gene on a chromosome means its:

• A. Position✓
• B. Function
• C. Start point
• D. End point

Explanation: The locus of a gene on a chromosome refers to its specific location or position on the chromosome. It is the precise point on the chromosome where the gene is situated, and it is usually described by its chromosomal coordinates (e.g., 3q21, meaning the gene is located on the long arm of chromosome 3, at position 21).

Q32. The carotenoids absorb light in the visible spectrum between _ and _ wavelengths.

• A. 400-600 nm
• B. 530-700 m
• C. 620-700 nm✓
• D. 500-600 nm

Explanation: Carotenoids are a group of pigments that absorb light in the visible spectrum, specifically in the range of 430-470 nanometers (nm). This range corresponds to the orange to red region of the visible spectrum.

Q33. The cells of the endoderm of Coelenterates are specialised for:

• A. Excretion
• B. Digestion✓
• C. Defense
• D. Respiration

Explanation: In Coelenterates (also known as Cnidarians), such as jellyfish, corals, and sea anemones, the endoderm (also known as the gastrodermis) is the innermost layer of cells that lines the digestive cavity. The cells of the endoderm are specialized for digestion, specifically:- Nutrient absorption- Enzyme secretion- Intracellular digestion (breaking down food particles within cells)The endoderm cells are responsible for:- Secreting digestive enzymes to break down food- Absorbing nutrients from the digested food- Eliminating waste products

Q34. Viruses are not classified based on:

• A. Morphology
• B. Host specificity
• C. Cell membrane✓
• D. Envelope

Explanation: Viruses are not classified based on the presence or absence of a cell membrane because:- Viruses do not have a cell membrane like cellular organisms do. Instead, they have a protein coat called a capsid that surrounds their genetic material.- Some viruses have an envelope, which is a lipid bilayer derived from the host cell membrane, but this is not a universal characteristic among viruses.

Q35. An additional covering surrounds the cell wall of some bacteria that either prevents the bacteria from being phagocytosed by host cells or helps them to make biofilm.Which of the following term is used for this covering?

• A. Capsule✓
• B. Slime
• C. Glycocalyx
• D. Spore

Explanation: The capsule is an additional covering that surrounds the cell wall of some bacteria, providing protection against:- Phagocytosis (engulfment by host cells)- Desiccation (drying out)- Antibiotics and other antimicrobial agentsThe capsule is composed of polysaccharides (complex sugars) and can be found in both Gram-positive and Gram-negative bacteria.

Q36. The protein coat surrounding the genome of virus is called:

• A. Capsid✓
• B. DNA sheath
• C. Phage
• D. Viroid

Explanation: The capsule is an additional covering that surrounds the cell wall of some bacteria, providing protection against phagocytosis (engulfment by host cells), desiccation (drying out), Antibiotics and other antimicrobial agentsThe capsule is composed of polysaccharides (complex sugars) and can be found in both Gram-positive and Gram-negative bacteria.

Q37. In the 'non-cyclic electron transport of light reaction', the deficit of _ electrons occur in the chlorophyll, as it absorbs energy

• A. 1
• B. 2✓
• C. 3
• D. 4

Explanation: In the non-cyclic electron transport of the light reaction, also known as the Z-scheme, the deficit of electrons occurs in the chlorophyll molecule (specifically, chlorophyll a) as it absorbs energy from light. This energy excites an electron, which is then transferred to a special molecule called an electron acceptor, leaving a deficit of two electrons in the chlorophyll molecule.

Q38. What is the number of carbon atoms in pyruvic acid?

• A. 8
• B. 2
• C. 3✓
• D. 4

Explanation: Pyruvic acid has the molecular formula C3H4O3. It has 3 carbon atoms.you can remember it by keeping in mind the fact that one glucose molecule splits into two pyruvic acid molecules in glycolysis. As glucose has 6 C-atoms, each pyruvate should have 3 C-atoms.

Q39. Sucrose is hydrolysed into:

• A. Lactose and Glucose
• B. Lactose and Fructose
• C. Glucose and fructose✓
• D. Glucose and galactose

Explanation: Sucrose, also known as table sugar, is a disaccharide that is hydrolyzed into two monosaccharides: glucose and fructose. This reaction is catalyzed by the enzyme sucrase:Sucrose (C12H22O11) → Glucose (C6H12O6) + Fructose (C6H12O6)

Q40. _ is the heat required to convert a gram of water into vapours at its boiling point.

• A. Heat of vapourization✓
• B. Specific heat capacity
• C. Heat of ionization
• D. Polarity of water

Explanation: The heat of vaporization is the amount of heat energy required to convert a unit mass of a substance (in this case, water) from its liquid phase to its vapor phase at its boiling point. For water, the heat of vaporization is approximately 2250 kJ/kg or 540 cal/g.

Q41. Which mode of genetic exchange between bacteria involves cell-to-cell contact between the bacterial cells?

• A. Transduction
• B. Transformation
• C. Conjugation✓
• D. Both a and b

Explanation: Conjugation is the process of genetic exchange between bacteria that involves direct cell-to-cell contact between the bacterial cells. It requires a specialized structure called a conjugation pilus, which allows the cells to attach and transfer DNA from one cell to another.

Q42. _ regulates the selective permeability of the plasma membrane, allowing movement of molecules according to the needs of the cells.

• A. Membrane proteins✓
• B. Membrane carbohydrates
• C. Membrane glycolipids
• D. Membrane cholesterol

Explanation: Membrane proteins regulate the selective permeability of the plasma membrane, allowing the movement of molecules according to the needs of the cell. These proteins can act as:- Channels: allowing certain molecules to pass through the membrane- Transporters: actively moving molecules across the membrane- Receptors: recognizing and binding to specific molecules, triggering responses- Enzymes: catalyzing reactions within the membraneMembrane proteins control the flow of molecules across the membrane, ensuring that the cell maintains homeostasis and regulates the exchange of nutrients, waste products, and signaling molecules.

Q43. The neuron is said to be polarized when the:

• A. Inside the plasma membrane has a negative energy compared to the outside✓
• B. Inside of the plasma membrane has a positive energy compared to the outside
• C. Inside the plasma membrane has the same energy compared to the outside
• D. Positive charge moves inside the neuron

Explanation: Neurons are said to be polarized when there is a difference in electrical potential between the inside and outside of the plasma membrane. This is known as the resting potential. In a polarized neuron, the inside of the plasma membrane has a negative electrical charge (about -70 millivolts) compared to the outside. This is due to a higher concentration of potassium ions (K+) inside the cell and a higher concentration of sodium ions (Na+) outside the cell. The negative charge inside the cell is also maintained by the selective permeability of the plasma membrane, which allows potassium ions to leave the cell more easily than sodium ions can enter.

Q44. Which part of the brain plays a key role in long-term memory?

• A. Thalamus
• B. Hippocampus✓
• C. Hypothalamus
• D. Amygdala

Explanation: The hippocampus is a structure in the temporal lobe that plays a critical role in the formation and consolidation of long-term memories, especially those related to emotions and experiences. It is involved in encoding new memories, consolidating information from short-term to long-term memory, and Spatial navigation and memory. Damage to the hippocampus can lead to difficulties in forming new memories, a condition known as anterograde amnesia.

Q45. Which of the following is an example of hydrolase:

• A. Transmethylase
• B. Oxygenase
• C. Peroxidases
• D. Phosphatase✓

Explanation: Hydrolases are a class of enzymes that catalyze the cleavage of chemical bonds using water. Phosphatase is an example of a hydrolase enzyme that removes phosphate groups from molecules by hydrolysis.

Q46. All of the following are true about neutrophils, EXCEPT:

• A. Most abundant form of WBC’s
• B. Have a short life span.
• C. Made by the thymus gland.✓
• D. Released by the bone marrow.

Explanation: Neutrophils are not made by the thymus gland. The thymus gland is responsible for the maturation and development of T-lymphocytes (a type of WBC), not neutrophils.

Q47. According to Neo-Darwinism, which of the following is a case of evolution?

• A. Reproductive isolation✓
• B. Infinite large population
• C. Environmental stability
• D. Both a and b

Explanation: Neo-Darwinism (Modern Synthetic Theory) explains evolution through the combined effects ofGenetic variation (mutation + recombination)Natural selectionIsolation, especially reproductive isolationWhen populations become reproductively isolated, gene flow stops. Over generations, different mutations accumulate in each group, causing genetic divergence and eventually the formation of new species — that is, evolution.

Q48. Darwin's "Origin of species by natural selection" is mainly concerned with:

• A. Origin of life
• B. Adaptation
• C. Extinction
• D. Speciation✓

Explanation: Charles Darwin's book "On the Origin of Species by Natural Selection" (1859) is primarily concerned with explaining the process of speciation, which is the formation of new species from existing ones. Darwin's theory of evolution by natural selection provides a mechanism for how species adapt and change over time, leading to the diversity of life on Earth.

Q49. The sinoatrial node is located in the _ wall of the right atrium.

• A. Lower dorsal
• B. Upper dorsal✓
• C. On the interatrial septum
• D. Near the coronary sinus

Explanation: The sinoatrial (SA) node, also known as the natural pacemaker, is located in the upper dorsal (posterior) wall of the right atrium, near the junction of the superior vena cava and the right atrium. It is a small group of specialized cardiac cells that generate electrical impulses, controlling the heart's rhythm and rate.

Q50. Where does the Trachea lie in relation to the esophagus?

• A. Dorsal
• B. Ventral✓
• C. Medial
• D. Lateral

Explanation: The trachea (windpipe) is located ventral (in front of) the esophagus in the thoracic cavity. In other words, the trachea is positioned anteriorly (in front) to the esophagus.

Q51. Which of the following is true about bradykinin?

• A. It is produced at the site of tissue injury.✓
• B. It has no role in the leakage of fluids into the tissues in inflammation.
• C. It destroys phagocytes.
• D. It produces interferon gamma.

Explanation: Bradykinin is a peptide hormone that plays a key role in the inflammatory response. It is produced at the site of tissue injury, where it is generated from kininogen by the action of kallikrein. Bradykinin then binds to specific receptors on blood vessels and other cells, leading to:- Increased vascular permeability (leakage of fluids into tissues)- Smooth muscle contraction- Pain transmission- Inflammation

Q52. Which of the following is a prokaryote?

• A. Protista
• B. E.coli✓
• C. Amoeba
• D. Fungi

Explanation: E. coli (Escherichia coli) is a type of bacteria, which is a prokaryote. Prokaryotes are single-celled organisms that lack a true nucleus and other membrane-bound organelles. They have a simple cell structure and are typically small in size.

Q53. Endospore formation is _

• A. A reproductive process
• B. A vegetative process✓
• C. Can be reproductive or vegetative depending on the conditions
• D. Is related to invading host cells

Explanation: Endospore formation is a survival mechanism used by certain bacteria, such as Bacillus and Clostridium species, to withstand harsh environmental conditions like high temperatures, radiation, and chemicals. During endospore formation, the bacterial cell undergoes a series of changes to produce a highly resistant, dormant cell called an endospore.Endospore formation is a vegetative process because it:- Involves the transformation of a single cell into a highly resistant form- Is not directly involved in reproduction or the production of new cells- Helps the bacterium survive adverse conditions, allowing it to remain dormant until favorable conditions return

Q54. Which among the following is NOT the role of Sertoli cells?

• A. Protect sperms
• B. Provides liquid medium to sperms
• C. Provides nourishment to sperms
• D. Secrete testosterone✓

Explanation: Sertoli cells do not secrete testosterone. Instead, they play a crucial role in supporting and nurturing developing sperm cells

Q55. At the beginning of the menstrual phase the _ are at the lowest level.

• A. Follicle stimulating harmone
• B. Gonadotrophins
• C. Ovarian hormones✓
• D. None of these

Explanation: At the beginning of the menstrual phase, the levels of ovarian hormones, specifically estrogen and progesterone, are at their lowest. This is because the corpus luteum, which produced these hormones during the previous menstrual cycle, has degenerated, and a new follicle has not yet matured to produce significant amounts of estrogen.

Q56. Which cartilage is found at the end of long bones?

• A. Calcified
• B. Elastic
• C. Fibrous
• D. Hyaline✓

Explanation: At the beginning of the menstrual phase, the levels of ovarian hormones, specifically estrogen and progesterone, are at their lowest. This is because the corpus luteum, which produced these hormones during the previous menstrual cycle, has degenerated, and a new follicle has not yet matured to produce significant amounts of estrogen.

Q57. How many actin filaments surround the myosin at each end?

• A. 2
• B. 4
• C. 6✓
• D. 8

Explanation: In a muscle sarcomere, each myosin filament (thick filament) is surrounded by 6 actin filaments (thin filaments) at each end. This arrangement allows for the sliding filament theory of muscle contraction, where the myosin heads bind to the actin filaments and pull them towards the center of the sarcomere, resulting in muscle contraction.

Q58. When are Rh antibodies produced in Rh-ve persons?

• A. Naturally before birth
• B. Naturally after birth
• C. After exposure to Rh antigen✓
• D. After exposure to Rh antibodies

Explanation: Rh antibodies are produced in Rh-negative (Rh-ve) individuals when they are exposed to Rh-positive (Rh+ve) blood, which contains the Rh antigen. This can occur in the following situations:1. Blood transfusion: Receiving Rh+ve blood can trigger the production of Rh antibodies in an Rh-ve person.2. Pregnancy: An Rh-ve mother carrying an Rh+ve fetus can be exposed to Rh+ve blood during delivery or miscarriage, leading to antibody production.3. Accidental exposure: In rare cases, exposure to Rh+ve blood through injuries or medical procedures can also trigger antibody production.Rh antibodies are not produced naturally before or after birth, but rather as an immune response to exposure to the Rh antigen.

Q59. Which of the following types of Haemophilia is more common in the human population?

• A. Haemophilia A✓
• B. Haemophilia B
• C. Haemophilia C
• D. Haemophilia VII

Explanation: Haemophilia A, also known as classic haemophilia, is the most common type of haemophilia, accounting for about 80-85% of all haemophilia cases. It is caused by a deficiency or dysfunction of factor VIII, a protein essential for blood clotting.Haemophilia A is an X-linked recessive disorder, meaning that the gene responsible for the condition is located on the X chromosome. This means that:- Males are more likely to be affected, as they have only one X chromosome- Females can be carriers, but are less likely to be affected, as they have two X chromosomes

Q60. Parazoa are simple multicellular animals which are believed to have evolved from?

• A. Bacteria
• B. Protists✓
• C. Fungi
• D. Plants

Explanation: Parazoa is a subkingdom of animals that includes simple multicellular organisms, such as sponges (Phylum Porifera). They are believed to have evolved from protist ancestors, specifically from single-celled flagellated protists.Protists are a diverse group of eukaryotic microorganisms that don't fit into any of the traditional kingdoms (Animalia, Plantae, Fungi, or Monera). They share characteristics with animals, such as motility and heterotrophy (obtaining energy by consuming other organisms), but lack true tissues and organs.The evolutionary transition from protists to parazoans likely involved the development of:1. Multicellularity2. Cell differentiation3. Simple tissue organization

Q61. Which structure is responsible for the excretion in Arthropods?

• A. Nephron
• B. Protonephridia
• C. Metanephridia
• D. Malpighian tubes✓

Explanation: Malpighian tubules are the primary excretory organs in arthropods, including:1. Insects (e.g., beetles, flies, bees)2. Arachnids (e.g., spiders, scorpions)3. Crustaceans (e.g., crabs, lobsters)These tubules remove waste products, such as nitrogenous compounds, from the hemolymph (arthropod equivalent of blood) and excrete them outside the body. Malpighian tubules are usually found in pairs and are connected to the digestive system.

Q62. Alternation of generation is the character of _ phylum?

• A. Arthropoda
• B. Annelida
• C. Coelantrata✓
• D. Echinodermata

Explanation: Alternation of generations is a life cycle characteristic of the phylum Cnidaria, which includes Jellyfish,Corals,Sea anemones,Hydra

Q63. Which of the following can be effective in preventing viral infection in humans?

• A. Taking antihistamines
• B. Getting vaccinated✓
• C. Applying antiseptics
• D. Taking antibiotics

Explanation: Vaccination is a highly effective way to prevent viral infections by:1. Introducing a small, harmless piece of the virus (antigen) to the body2. Stimulating the immune system to produce antibodies and immune cells that recognize and fight the virus3. Providing long-term immunity against specific viruses

Q64. Purines are _ nitrogenous bases.

• A. Double ringed✓
• B. Single ringed
• C. Double bond
• D. Single bond

Explanation: Purines are a type of nitrogenous base found in DNA and RNA, characterized by a double-ring structure. The two purine bases found in DNA and RNA are:1. Adenine (A)2. Guanine (G)Both adenine and guanine have a double-ring structure, consisting of a nine-membered purine ring.

Q65. What is 'Flavin adenine dinucleotide’?

• A. Catalyst
• B. Coenzyme✓
• C. Cofactor
• D. Enzyme

Explanation: Flavin adenine dinucleotide (FAD) is a coenzyme, a non-protein molecule that assists enzymes in catalyzing various biochemical reactions. FAD is a derivative of riboflavin (vitamin B2) and plays a crucial role in energy metabolism, particularly in the electron transport chain.FAD can exist in two forms:1. FAD (oxidized form)2. FADH2 (reduced form)FAD acts as an electron carrier, accepting and donating electrons during metabolic reactions, such as:- Cellular respiration- Fatty acid oxidation- Citric acid cycle

Q66. The cerebellum is primarily concerned with:

• A. Thinking and reasoning
• B. Balancing during active movement✓
• C. Temperature regulation
• D. Initiation of muscular contraction

Explanation: The cerebellum is a region in the hindbrain that plays a crucial role in motor coordination, balance, and learning new motor skills. Its primary functions include: Motor coordination: The cerebellum integrates sensory information and motor signals to coordinate movements, ensuring smooth and precise actions. Balance and equilibrium: The cerebellum helps maintain posture, balance, and equilibrium by regulating muscle tone and movement. Learning new motor skills: The cerebellum is involved in the learning and consolidation of new motor skills, such as riding a bike or playing a musical instrument.

Q67. Adding substrates will NOT make a difference to the enzyme catalysed reaction:

• A. When few enzyme molecules are left unsaturated.✓
• B. When the substrate cools down.
• C. When the substrate heats up.
• D. When many enzyme molecules remain unsaturated.

Explanation: The rate of an enzyme-catalysed reaction increases with substrate concentration only until all the enzyme’s active sites are occupied. Once most of the enzyme molecules are saturated with substrate, the reaction reaches its maximum rate (Vmax). Beyond this point, adding more substrate does not increase the rate because there are no free enzyme molecules left to bind with it.If many enzymes are still unsaturated, adding substrate will still increase the rate. But when only a few enzyme molecules are unsaturated (i.e., almost all are occupied), adding more substrate makes no difference.

Q68. All animals begin life as a _.

• A. Multicellular fertilised egg
• B. Single fertilised egg✓
• C. Hollow blastula
• D. Gastrula

Explanation: All animals, from simple sponges to complex humans, begin their lives as a single fertilized egg cell, also known as a zygote. This zygote is formed when a sperm fertilizes an egg cell, resulting in a single cell with a unique combination of genetic material from both parents.From this single cell, the embryo develops through various stages, including:1. Cleavage: The zygote divides into multiple cells.2. Blastula: A hollow ball of cells forms.3. Gastrula: The blastula undergoes invagination, forming a multilayered embryo.So, while all animals do pass through the blastula and gastrula stages, they all begin life as a single fertilized egg.

Q69. X is a compound that do not react with Na metal but produces carboxylic acid when heated under reflux with acidified potassium dichromate?

• A. Propanal✓
• B. Propanone
• C. Propan-1-ol
• D. Propan-2-ol

Explanation: The correct answer is Propanal because it is an aldehyde that does not react with sodium metal and can be oxidized to propanoic acid when treated with potassium dichromate under acidic conditions. The other options do not satisfy the criteria given in the question:Propanone (Option B) is a ketone that does not oxidize to a carboxylic acid under the specified conditions, so it is incorrect.Propan-1-ol (Option C) is a primary alcohol that reacts with sodium metal, thus failing the first condition of the question.Propan-2-ol (Option D) is a secondary alcohol that also reacts with sodium metal, making it unsuitable as well.Thus, only Propanal correctly fits both criteria of the question.

Q70. Which reaction will proceed in forward direction?

• A. Kc=10✓
• B. Kc=1
• C. Kc=1/10
• D. Kc=1/100

Explanation: The value of Kc (equilibrium constant) determines the direction of a reaction. A Kc value greater than 1 indicates that the reaction favors the products, and the reaction will proceed in the forward direction.

Q71. Which pair of ions have five unpaired d-electrons?

• A. Fe+2 and Mn+2
• B. Fe+2 and Mn+3
• C. Fe+3 and Mn+3
• D. Fe+3 and Mn+2✓

Explanation: Here's a breakdown of the electron configurations for each ion:Fe+3: [Ar] 3d5Mn+2: [Ar] 3d5As you can see, both ions have 5 unpaired electrons in their d orbitals

Q72. Which one the following is a Nucleophile.

• A. H2O✓
• B. AlCl3
• C. BF3
• D. Cl2

Explanation: A nucleophile is a species that donates a pair of electrons to form a covalent bond with an electrophile. Water (H2O) is a nucleophile because it has a lone pair of electrons on the oxygen atom, which can be donated to form a bond.

Q73. Which one is more metallic?

• A. Na
• B. Mg
• C. Cs✓
• D. K

Explanation: The metallic character of elements increases down a group (column) in the periodic table. Caesium (Cs) is in group 1, period 6, making it the most metallic among the options.

Q74. Which of the following spectral lines series lies in the visible Region?

• A. Lyman series
• B. Balmer series✓
• C. Pfund series
• D. Brackett series

Explanation: The Balmer series is a series of spectral lines in the hydrogen atom spectrum that lies in the visible region of the electromagnetic spectrum, with wavelengths between 400-700 nanometers (nm). This series corresponds to electron transitions from higher energy levels (n ≥ 3) to the second energy level (n = 2).

Q75. Which of the following represents the functional group of acid halides?

• A. R-OH
• B. R-COX✓
• C. R-X
• D. R-COOH

Explanation: The functional group of acid halides is represented by R-COX, where:- R is an organic group (alkyl or aryl)- C is the carbon atom- O is the oxygen atom- X is the halogen atom (Cl, Br, I, or F)Acid halides, also known as acyl halides, are compounds that contain this functional group. They are reactive derivatives of carboxylic acids and are used in various organic synthesis reactions.

Q76. Which of the following prefixes is used when two methyl groups are attached with the second last carbon of alkane chain?

• A. n-
• B. iso-
• C. neo-✓
• D. geminal-

Explanation: The prefix neo- refers to a substituent whose second-to-last carbon of the chain is trisubstituted (has three methyl groups attached to it). A neo-pentyl has five carbons total. This is kind of correct option although germinal can be correct but it asked for prefix so this is correct option

Q77. Which of the following organic acid does NOT have a COOH group?

• A. Acetic acid
• B. Ascorbic acid
• C. Butyric acid
• D. Picric acid✓

Explanation: Picric acid (2,4,6-trinitrophenol) does not have a COOH group. Instead, it has a phenol group (-OH) with three nitro groups (-NO2) attached to the benzene ring.

Q78. Which of the following cell reactions correctly represent the electrolysis of water?

• A. 2H+ + 2e –->H2(g)
• B. 2H2O +2e —> H2(g)+2(OH-)
• C. 2(OH-) —> 2H2O + O2(g) +4e
• D. 2H2O —> O2(g) +4H+ + 4e✓

Explanation: Here's a breakdown of the electrolysis of water:Cathode: Water is reduced to hydrogen gas. 2H+ + 2e- -> H2(g) Anode: Water is oxidized to oxygen gas. 2H2O -> O2(g) + 4H+ + 4e- The overall reaction is the sum of these two half-reactions:2H2O -> 2H2(g) + O2(g)Therefore, the correct answer is d, which represents the overall reaction at the anode.

Q79. Which method is generally used to prepare alkynes?

• A. Dehydrohalogenation of vicinal dihalide✓
• B. Hydrogenation of alkene
• C. Hydrolysis
• D. Hydration of alkene

Explanation: Dehydrohalogenation is a reaction where a vicinal dihalide (a compound with two halogen atoms on adjacent carbon atoms) is converted into an alkyne. This is typically done using a strong base, such as potassium hydroxide (KOH), to remove two molecules of hydrogen halide (HX) and form a triple bond between the carbon atoms.The general reaction is:RCHX-CHXR' → R-C≡C-R' + 2HXThis method is commonly used to prepare alkynes because it allows for the formation of the triple bond with good yields and selectivity.

Q80. Which compound is formed when Magnesium is reacted with 2 molecules of water?

• A. Mg(OH)2✓
• B. Mg(OH)
• C. MOH
• D. Mg(OH)3

Explanation: When magnesium (Mg) reacts with two molecules of water (H2O), it forms magnesium hydroxide (Mg(OH)2). The reaction is:Mg + 2H2O → Mg(OH)2 + H2Magnesium hydroxide is a white solid that is insoluble in water. It is a strong base and is often used in antacids and laxatives.

Q81. When an element occurs in different physical forms it is called _.

• A. Anisotropy
• B. Isomorphism
• C. Polymorphism
• D. Allotropy✓

Explanation: Allotropy refers to the ability of an element to exist in different physical forms, often with different crystal structures or molecular arrangements. This can result in different properties, such as density, hardness, or color. Examples of allotropes include:- Carbon: diamond, graphite, and fullerenes- Sulfur: orthorhombic, monoclinic, and rhombic forms- Phosphorus: white, black, and red forms

Q82. What mass of CaCO3 gives 48.8 litres (measured at STP) of CO2, on strong heating?_.

• A. 100g
• B. 150g
• C. 200g✓
• D. 300g

Explanation: Write the balanced chemical equation: CaCO3(s) -> CaO(s) + CO2(g)Calculate the moles of CO2:At STP, 1 mole of any gas occupies 22.4 liters.So, moles of CO2 = 48.8 L / 22.4 L/mol = 2.18 molesUse the mole ratio from the balanced equation:1 mole of CaCO3 produces 1 mole of CO2. So, moles of CaCO3 = 2.18 molesCalculate the mass of CaCO3:Molar mass of CaCO3 = 40.08 g/mol + 12.01 g/mol + (3 * 16.00 g/mol) = 100.09 g/mol Mass of CaCO3 = moles * molar mass = 2.18 moles * 100.09 g/mol = 218.2 gTherefore, the mass of CaCO3 that gives 48.8 liters of CO2 at STP is approximately 218.2 grams.

Q83. What is the reason of small atomic radii of sodium ions as compared to sodium atom?

• A. Electronegativity
• B. Effective nuclear charge✓
• C. Shielding effect
• D. Electron affinity

Explanation: The atomic radius of a sodium atom is 186 pm, while the ionic radius of a sodium ion (Na+) is 95 pm. The smaller radius of the sodium ion is due to the effective nuclear charge, which is the net positive charge experienced by the outermost electrons.When a sodium atom loses an electron to form a sodium ion, the number of electrons decreases, but the number of protons in the nucleus remains the same. This results in an increased effective nuclear charge, which pulls the remaining electrons closer to the nucleus, reducing the ionic radius.

Q84. What is the radius of 3rd orbit of electron in H- atom.

• A. 3.39A
• B. 4.761A✓
• C. 5.29 x 10^11 A
• D. 9.7A

Explanation: The radius of an electron orbit in a hydrogen atom can be calculated using the Bohr model, which gives the radius of the nth orbit as:rn = n² × 0.529 Åwhere n is the principal quantum number.For the 3rd orbit, n = 3, so:r₃ = 3² × 0.529 Å= 9 × 0.529 Å= 4.76 Å

Q85. What is the other name for Positive rays?

• A. Canal rays✓
• B. Magnetic rays
• C. Quantum
• D. Photon rays

Explanation: Positive rays, also known as canal rays, are streams of positively charged particles, typically ions or cations, that are produced when a high voltage is applied to a gas-filled tube. They were first observed by Eugen Goldstein in 1886 and are also known as canal rays because they pass through the cathode's canal-like structure

Q86. The Volume of a fixed mass of gas is directly proportional to absolute temperature and constant pressure as stated by:

• A. Daltons Law
• B. Boyle's Law
• C. Avogadro's Law
• D. Charles law✓

Explanation: Charles' Law states that, at constant pressure, the volume of a fixed mass of gas is directly proportional to the absolute temperature. This can be expressed mathematically as:V ∝ TorV = kTwhere V is the volume, T is the absolute temperature, and k is a constant

Q87. The tautomer of propenol is

• A. Propanal
• B. Propanone✓
• C. Methyl ethyl ether
• D. Butanone

Explanation: Propenol (CH₃CH=CHOH) is a tautomer of propanone (CH₃COCH₃), also known as acetone. Tautomers are molecules that can easily interconvert through the movement of a proton (H+ ion) or a group of atoms.In this case, propenol can tautomerize to propanone through the following reaction:CH₃CH=CHOH ⇌ CH₃COCH₃

Q88. The substituent attached to the benzene ring that act as Ring deactivator is.

• A. NO2✓
• B. COOH
• C. Cl
• D. NH3

Explanation: A ring deactivator is a substituent that reduces the reactivity of the benzene ring towards electrophilic substitution reactions. NO2 (nitro group) is a strong ring deactivator because it:- Withdraws electrons from the ring through resonance- Has a negative inductive effect, reducing the electron density in the ring

Q89. The specific heat of water is.

• A. 4.2 kJ/mol/K
• B. 4.2 j/g.K✓
• C. 4.61/g/K
• D. 42/g/K

Explanation: The specific heat capacity of water is approximately 4.2 joules per gram per degree Celsius (J/g/°C). This means that it takes 4.2 joules of energy to raise the temperature of 1 gram of water by 1 degree Celsius.

Q90. The SI unit of pressure is.

• A. Pascal✓
• B. mmHg
• C. torr
• D. atm

Explanation: The Pascal (Pa) is the SI unit of pressure, defined as one newton per square meter (N/m²). It is a measure of the force applied per unit area.

Q91. The reactant which consumes first in a chemical reaction is called?

• A. Consumed reactant
• B. Limiting reactant✓
• C. Excess reactant
• D. Non-reacted reactant

Explanation: The limiting reactant is the reactant that is consumed first in a chemical reaction, thereby limiting the amount of product that can be formed. It is the reactant that is present in the smallest stoichiometric amount, relative to the other reactants.

Q92. The number of particles (atoms, molecules, tons) in one mole of any substance is numerically equal to

• A. 6.023x10^22
• B. 6.023x10^21
• C. 6.023x10 ^23✓
• D. 4.02x10^23

Explanation: One mole of any substance contains 6.023 x 10^23 particles (atoms, molecules, or ions). This number is known as the Avogadro's number (NA).Avogadro's number is a fundamental constant in chemistry, and it is used to relate the amount of a substance to the number of particles it contains.

Q93. The final substitution product in the Chlorination of methane in the presence of UV light and excess chlorine is.

• A. Methylene chloride
• B. Carbon tetrachloride✓
• C. Methylene dichloride
• D. Chloroform

Explanation: The chlorination of methane in the presence of UV light and excess chlorine is a substitution reaction that proceeds through a series of steps, ultimately leading to the formation of carbon tetrachloride (CCl4).The reaction sequence is:CH4 → CH3Cl → CH2Cl2 → CHCl3 → CCl4

Q94. The element chlorine is found in a gaseous state while bromine is found in:

• A. Solid state
• B. Liquid state✓
• C. Crystalline form
• D. Condensed form

Explanation: At room temperature and atmospheric pressure, chlorine (Cl2) is a yellow-green gas, while bromine (Br2) is a reddish-brown liquid. Bromine is one of the few elements that is liquid at room temperature.

Q95. The correct sequence according to acidity of alcohols is.

• A. Primary > Secondary >Tertiary.✓
• B. Tertiary > Secondary > Primary
• C. Secondary > Primary >Tertiary
• D. Primary < Secondary < Tertiary

Explanation: This sequence is due to the following factors:Inductive Effects: In primary alcohols, there are fewer alkyl groups attached to the carbon bearing the hydroxyl group (-OH). Fewer alkyl groups mean less electron-donating inductive effect, which stabilizes the alkoxide ion by making it less negative. In contrast, tertiary alcohols have more alkyl groups, which destabilize the alkoxide ion by donating electron density, thus making tertiary alcohols less acidic.Steric Effects: Tertiary alcohols are more sterically hindered, which makes it more difficult for solvent molecules to stabilize the alkoxide ion through hydrogen bonding. This steric hindrance also lowers the acidity.

Q96. The correct order of reactivity of alkyl halides is.

• A. R-Br > R-CL > R-F > R-I
• B. R-Br > R-F > R-I > R-CI
• C. R-I > R-Br > R-Cl > R-F✓
• D. R-Cl > R-I > R-Br > R-F

Explanation: The reactivity of alkyl halides towards nucleophilic substitution reactions follows the order:R-I (alkyl iodide) > R-Br (alkyl bromide) > R-Cl (alkyl chloride) > R-F (alkyl fluoride)This order is based on the strength of the carbon-halogen bond, with the weaker bonds being more reactive. The bond strength decreases from R-F (strongest) to R-I (weakest), making R-I the most reactive and R-F the least reactive

Q97. The bond that determines the secondary structure of protein is:

• A. Coordinate bond
• B. Covalent bond
• C. Hydrogen bond✓
• D. Ionic bond

Explanation: Hydrogen bonds play a crucial role in determining the secondary structure of proteins. They are weak electrostatic attractions between the positively charged hydrogen atoms and negatively charged oxygen or nitrogen atoms in the peptide backbone. These bonds help stabilize the alpha helix and beta sheet structures, which are the two main types of secondary structures in proteins

Q98. Super batteries with high charge density are also called:

• A. Primary batteries
• B. Secondary batteries✓
• C. Solar batteries
• D. Fuel batteries

Explanation: Secondary batteries, also known as rechargeable batteries, have high charge density and are designed to be reused multiple times. They can be charged, discharged, and recharged many times, making them a popular choice for applications where battery longevity is important. Examples of secondary batteries include lead-acid batteries, lithium-ion batteries, and nickel-cadmium batteries.

Q99. Silver Mirror with Tollens Reagent is formed by

• A. Acid halides
• B. Alcohols
• C. Aldehydes✓
• D. Ketones

Explanation: Tollens' reagent, also known as the silver mirror test, is a chemical test used to detect the presence of aldehydes. When an aldehyde is treated with Tollens' reagent (a solution of silver nitrate and ammonia), a silver mirror is formed on the inner surface of the test tube. This is due to the reduction of silver ions by the aldehyde, resulting in the formation of metallic silver.

Q100. Select the correct IUPAC name among the following:

• A. 2-Bromo-4-chloro-3-lodopentane✓
• B. 4-Bromo-2-chloro-3-lodopentane
• C. 4 Bromo-2 iodo-3-chloropentane
• D. 2-Chloro-3-iodo-4-bromopentane

Explanation: The IUPAC name is determined by the following rules:1. Number the carbon atoms in the chain, starting from the end closest to the functional group (in this case, the halogens).2. Identify the substituents (halogens) and their positions on the chain.3. List the substituents in alphabetical order, with their positions.In this case, the correct order is:- 2-Bromo (Br at position 2)- 4-Chloro (Cl at position 4)- 3-Iodo (I at position 3)

Q101. Oxidation of Secondary alcohol gives which of the following products?

• A. Aldehydes
• B. Carboxylic acids
• C. Ester
• D. Ketone✓

Explanation: The oxidation of a secondary alcohol typically results in the formation of a ketone. This is because the secondary alcohol has two alkyl groups attached to the carbon atom bearing the hydroxyl group, which makes it difficult to oxidize further to a carboxylic acid.The general reaction is:R₂CHOH → R₂CO (ketone)

Q102. One molecule of oxygen has the same mass as

• A. 8 moles of O2
• B. 16 moles of H
• C. 2 molecules of CH
• D. One atom of Sulphur✓

Explanation: One molecule of oxygen (O2) has a molecular mass of approximately 32 atomic mass units (amu). Therefore, it corresponds to 32 grams per mole. A gram atom of sulfur also has a mass of 32 grams because the atomic mass of sulfur is 32, making it equivalent to one molecule of oxygen in terms of mass. The other options are incorrect because they either involve incorrect mole-to-mass calculations or involve molecules that do not match the molecular mass of oxygen's single molecule.

Q103. Lucas test is based on?

• A. Order of reaction
• B. Condition of reaction
• C. Molecularity of reaction
• D. Rate of reaction✓

Explanation: Lucas test is based on the rate of reaction of alcohols with Lucas reagent. It distinguishes alcohols by how quickly they form alkyl halides.

Q104. Increasing the compressibility of a gas (Z) decreases its.

• A. Pressure
• B. Volume✓
• C. Temperature
• D. Concentration

Explanation: The compressibility factor (Z) is a measure of how much a gas deviates from ideal gas behavior. A higher compressibility factor indicates that the gas is more compressible, meaning it can be compressed to a smaller volume than an ideal gas under the same conditions.Increasing the compressibility of a gas (Z) means that the gas can be compressed to a smaller volume, which decreases its volume (b).

Q105. In the IUPAC system Carboxylic acid is also called _

• A. Akinoic acid
• B. Alkanoic acid✓
• C. Alkenoic acid
• D. Alkyl alkanoate

Explanation: In the IUPAC system, carboxylic acids are also known as alkanoic acids. The suffix "-oic acid" is replaced with "-anoic acid" to indicate the presence of a carboxyl group (-COOH) in the molecule.For example:- Methanoic acid (HCOOH)- Ethanoic acid (CH₃COOH)- Propanoic acid (CH₃CH₂COOH)

Q106. The Wolff-Kishner reduction is carried out under whichconditions?

• A. Acidic
• B. Basic✓
• C. Neutral
• D. Anhydrous

Explanation: The Wolff-Kishner reduction is a chemical reaction that reduces aldehydes and ketones to their corresponding hydrocarbons. The reaction is typically carried out in the presence of:- Hydrazine (N2H4)- Sodium or potassium hydroxide (NaOH or KOH)- Ethylene glycol (or another high-boiling-point solvent)The reaction involves the formation of a hydrazone intermediate, which is then reduced to the corresponding hydrocarbon.

Q107. In following molecules which one has the shortest C-C bond length?

• A. C3H8
• B. C2H6
• C. C2H4
• D. C2H2✓

Explanation: The bond lengths in the given molecules are:- C3H8 (propane): 1.54 Å (single bond)- C2H6 (ethane): 1.53 Å (single bond)- C2H4 (ethylene): 1.33 Å (double bond)- C2H2 (acetylene): 1.20 Å (triple bond)The shortest C-C bond length is found in acetylene (C2H2), which has a triple bond between the two carbon atoms. This is because triple bonds are shorter than double bonds, which are shorter than single bonds.

Q108. In crystalline structure, when the length of all axes and angles are unequal then crystal will be.

• A. Cubic
• B. Monoclinic
• C. Orthorhombic
• D. Triclinic✓

Explanation: In crystallography, the crystal system is determined by the lengths of the axes and the angles between them. The triclinic crystal system is characterized by:- All axes (a, b, and c) are of unequal length- All angles (α, β, and γ) are of unequal measure and not equal to 90°This means that the crystal has no symmetry or repeating pattern, and the axes are not perpendicular to each other.

Q109. In a rate equation, rate=k[A] [B], the reaction is

• A. Zero order
• B. First order
• C. Second order✓
• D. Third order

Explanation: IThe rate equation rate = k[A][B] indicates that the reaction rate depends on the concentrations of two reactants, A and B. This is a characteristic of a second-order reaction.In a second-order reaction, the rate is proportional to the product of the concentrations of two reactants. This can be further classified into two types:- Second-order first-degree (rate = k[A][B], where A and B are different reactants)- Second-order second-degree (rate = k[A]^2, where A is the only reactant)

Q110. If the work is done by the system on the surroundings and heat is absorbed by the system from the surroundings the change in internal energy E will be

• A. E = q+w
• B. E = q+(-w)✓
• C. E= (-q)+(-w)
• D. E = (-q)+w

Explanation: According to the first law of thermodynamics:ΔE=q+wq = heat absorbed by the system (positive if absorbed, negative if released)w= work done on the system (positive if surroundings do work on the system, negative if system does work on surroundings)Now in this question:The system absorbs heat → q=+qThe system does work on surroundings → w= −w So,ΔE=q+(−w)ΔE=q−w

Q111. Humans are unable to digest:

• A. Starch
• B. Denatured protein
• C. Cellulose✓
• D. Fructose

Explanation: Humans are unable to digest cellulose, a type of complex carbohydrate (fiber) found in plant cell walls, due to the lack of the enzyme cellulase in our digestive system. Cellulase breaks down cellulose into simpler sugars, but since we don't produce it, cellulose passes through our digestive system undigested.

Q112. H2O has geometry:

• A. Regular tetrahedron
• B. Linear
• C. Distorted tetrahedral✓
• D. Pyramidal

Explanation: H₂O has a bent or V-shaped geometry, more specifically, it’s often described as distorted tetrahedral due to the two lone pairs on oxygen.Because of the lone pairs, the ideal tetrahedral angle (109.5°) is reduced to about 104.5°, making it distorted tetrahedral.

Q113. Greater the resonance energy of a molecule?

• A. Higher will be its reactivity.
• B. Lower will be its stability
• C. Higher will be its stability.✓
• D. Higher will be its density.

Explanation: Resonance energy is the energy released when a molecule adopts a resonating structure, which is a delocalized arrangement of electrons. A higher resonance energy indicates a greater degree of delocalization, leading to:- Increased stability: The molecule is more stable due to the dispersal of electrons, reducing the energy of the system.- Lower reactivity: The delocalized electrons are less available for reactions, making the molecule less reactive.

Q114. For an endothermic reaction, H represents the enthalpy of reaction. The minimum value for the energy for activation will?

• A. Equal to delta H
• B. More than delta H✓
• C. Less than delta H
• D. Zero

Explanation: For an endothermic reaction, the enthalpy of reaction (ΔH) is positive, indicating that energy is absorbed during the reaction. The activation energy (Ea) is the minimum energy required for the reaction to occur.Since the reaction is endothermic, the activation energy must be greater than the enthalpy of reaction (ΔH) to ensure that the reaction can proceed. This is because the system needs to overcome the energy barrier (Ea) to absorb the energy (ΔH) required for the reaction.

Q115. Flame tests identify alkali metals when they are burnt, which of the combinations given is the correct one?

• A. Li: Red✓
• B. Na: Lilac
• C. K: Red
• D. Cs: Yellow

Explanation: Flame tests are used to identify alkali metals based on the characteristic colors they produce when burned:- Lithium (Li): Red- Sodium (Na): Yellow- Potassium (K): Violet- Caesium (Cs): Blue

Q116. Enantiomers are examples of

• A. Cis Isomers
• B. Trans Isomers
• C. Optical Isomers✓
• D. Geometric isomers

Explanation: Enantiomers are pairs of molecules that are mirror images of each other, but are not superimposable. They have the same molecular formula, bond sequence, and functional groups, but differ in the three-dimensional arrangement of their atoms. This difference in arrangement leads to differences in their optical properties, such as rotation of plane-polarized light.Enantiomers are a type of stereoisomer, and are specifically known as optical isomers

Q117. Compound X reacts with Grignard's reagent to produce tertiary alcohols. What is the compound?

• A. Aldehyde
• B. Ketone✓
• C. Acid halide
• D. Carboxylic acid

Explanation: Grignard's reagent (RMgX) reacts with ketones to produce tertiary alcohols. The reaction involves the nucleophilic addition of the Grignard reagent to the carbonyl group of the ketone, followed by hydrolysis to form a tertiary alcohol.The reaction is:R2C=O (ketone) + RMgX (Grignard reagent) → R2C(OH)R' (tertiary alcohol)

Q118. Brass is an alloy of

• A. Copper and Iron
• B. Copper and Mg
• C. Copper and Zinc✓
• D. Copper and Silver

Explanation: Brass is a binary alloy composed of copper (Cu) and zinc (Zn). The proportion of copper and zinc can vary, but it is typically a combination of 60-70% copper and 30-40% zinc. The addition of zinc to copper produces an alloy with improved strength, corrosion resistance, and ductility compared to pure copper.

Q119. An unknown element having electronic configuration [Ne] 5s2 5p5 will be.

• A. Metal of II-A group
• B. Metalloid of V-A group
• C. Non-metal of VII-A group✓
• D. Non-metal of V-A group

Explanation: The electronic configuration [Ne] 5s2 5p5 indicates that the unknown element has:- A noble gas core (Ne)- 2 electrons in the 5s orbital- 5 electrons in the 5p orbitalThis configuration corresponds to a halogen, specifically Astatine (At), which is a non-metal in group VII-A (17) of the periodic table.

Q120. Amount of heat absorbed, when one mole of liquid changes to gas at its boiling point is called:

• A. Molar heat of sublimation
• B. Heat of vaporisation✓
• C. Latent heat of fusion
• D. Heat capacity

Explanation: The heat of vaporization is the amount of heat energy required to change one mole of a liquid into a gas at its boiling point, without any change in temperature. This process occurs at the boiling point, where the liquid is converted into vapor.

Q121. A well-known physical change is melting of ice. The melting of ice is favoured by:

• A. Low Pressure, High Temperature✓
• B. Low Temperature, High Pressure
• C. High Temperature, High Pressure
• D. Low Temperature, Low Pressure

Explanation: Low pressure reduces the melting point of ice, and high temperature provides the energy needed to overcome the hydrogen bonds holding the ice structure together. This combination facilitates the transition from solid to liquid. Other combinations either stabilize the solid form or do not provide enough energy for melting, making them less effective in favoring the melting process.

Q122. _ law states that the magnitude of the force between 2-point charges is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance between them.

• A. Ohm's law
• B. Gauss law
• C. Coulomb's law✓
• D. Lenz law

Explanation: Coulomb's law states that the magnitude of the electrostatic force (F) between two point charges (q1 and q2) is directly proportional to the product of the magnitudes of the charges and inversely proportional to the square of the distance (r) between them:F ∝ (q1 × q2) / r²orF = k × (q1 × q2) / r²where k is Coulomb's constant.

Q123. A ball thrown vertically upwards will have constant _ and a varying _

• A. Velocity and acceleration
• B. Kinetic energy, velocity
• C. Acceleration, velocity✓
• D. Kinetic energy and acceleration

Explanation: When a ball is thrown vertically upwards, it experiences a constant acceleration due to gravity, which is approximately -9.8 m/s². This acceleration acts downward, opposite to the direction of the ball's initial motion. Consequently, the ball's velocity changes as it rises and falls. Initially, the velocity decreases as the ball moves upwards, reaching zero at the peak of its motion. As the ball falls back down, the velocity increases in the downward direction. Therefore, the correct answer is that the ball has constant acceleration and varying velocity.Other options are incorrect because:Velocity and acceleration: Velocity is not constant; it changes due to gravity.Kinetic energy, velocity: Kinetic energy changes, but cannot be paired with a constant velocity.Kinetic energy and acceleration: Kinetic energy changes, but acceleration due to gravity is constant.

Q124. A boy raises an object of mass 10Kg vertically above his head through a height of 5m. The potential energy stored in the body is:_

• A. 98 J
• B. 49J
• C. 490 J✓
• D. 980 J

Explanation: The potential energy (PE) stored in an object is calculated as:PE = m × g × hwhere:m = mass of the object (10 kg)g = acceleration due to gravity (approximately 9.8 m/s²)h = height through which the object is raised (5 m)Substituting the values, we get:PE = 10 kg × 9.8 m/s² × 5 m= 490 J

Q125. A magnet is suspended from a spring and it oscillates in and out of a coil placed vertically below it. A galvanometer is connected to the coil and it shows?

• A. No deflection
• B. Deflection on one side only
• C. Deflection to the left and right with constant amplitude
• D. Deflection to the left and right with decreasing amplitude✓

Explanation: As the magnet oscillates in and out of the coil, it induces an electromotive force (EMF) in the coil due to the changing magnetic flux. This induced EMF causes a current to flow in the coil, which is detected by the galvanometer.The galvanometer will show:- Deflection to the left when the magnet is moving into the coil (increasing magnetic flux)- Deflection to the right when the magnet is moving out of the coil (decreasing magnetic flux)The amplitude of the deflection will decrease over time due to the damping of the oscillations (energy loss due to friction, air resistance, etc.).

Q126. A man standing in an elevator on the third floor of a building. What is the primary factor that determines the man's kinetic energy?

• A. His height above the ground
• B. His mass
• C. Elevator's speed✓
• D. Elevator's direction of movement

Explanation: The primary factor that determines the man's kinetic energy is the elevator's speed. Kinetic energy (KE) is given by the formula:KE = (1/2) × m × v²where:m = mass of the man (which remains constant)v = velocity (speed) of the elevatorSince the man is standing in the elevator, his velocity is the same as the elevator's velocity. Therefore, the elevator's speed is the primary factor that determines the man's kinetic energy.

Q127. A resistor has a resistance of 200 ohms. If a current of 0.5 amperes flows through it, what is the voltage drop across the resistor?

• A. 100 volts✓
• B. 110 volts
• C. 120 volts
• D. 0.002 volts

Explanation: The voltage drop across the resistor can be calculated using Ohm's Law:V = I × Rwhere:V = voltage drop (in volts)I = current (in amperes)R = resistance (in ohms)Given values:I = 0.5 AR = 200 ΩSubstituting the values, we get:V = 0.5 A × 200 Ω= 100 V

Q128. A three-dimensional image of remarkable quality can be achieved by modern version of microscope called:

• A. Compound microscope
• B. Simple microscope
• C. Transmission electron microscope
• D. Scanning electron microscope✓

Explanation: The Scanning Electron Microscope (SEM) produces high-resolution, three-dimensional images of surfaces by scanning a focused beam of electrons across the sample. The SEM can achieve remarkable image quality, with resolution down to 1-10 nanometers, and a large depth of field, making it ideal for studying surface topography and morphology

Q129. A train travels on a straight track passing signal A at 20 m/s. It accelerates uniformly at 2 m/s^2 and reaches signal B 100m further than A. At B the velocity of the train in m/s is

• A. 10
• B. 20
• C. 28✓
• D. 56

Explanation: Using the equation of motion:v² = u² + 2aswhere:v = final velocity (at signal B)u = initial velocity (at signal A) = 20 m/sa = acceleration = 2 m/s²s = distance between signals A and B = 100 mSubstituting the values, we get:v² = (20)² + 2(2)(100)v² = 400 + 400v² = 800v = √800v ≈ 28.28 m/sRounding to the nearest whole number, the velocity at signal B is approximately 28 m/s

Q130. A wave is characterised by the physical parameters:

• A. Amplitude, wavelength and acceleration
• B. Frequency, wavelength and acceleration
• C. Wavelength, frequency and speed of wave✓
• D. Displacement, wavelength and speed of wave

Explanation: A wave is typically characterized by the following physical parameters:1. Wavelength (λ): The distance between two consecutive points on the wave that are in phase with each other.2. Frequency (f): The number of oscillations or cycles of the wave per second.3. Speed of wave (v): The distance traveled by the wave per unit time.These three parameters are related by the wave equation:v = λf

Q131. Accelerating electromagnetic charges radiate electromagnetic waves which propagate at the

• A. speed of electromagnetic waves
• B. Frequency of light
• C. speed of light✓
• D. Frequency of electromagnetic waves

Explanation: Accelerating electromagnetic charges, such as electrons, radiate electromagnetic waves, which are a combination of electric and magnetic fields. These waves propagate through the electromagnetic field at a constant speed, which is:c = 299,792,458 meters per second (m/s)This speed is known as the speed of light, and it is a fundamental constant of the universe

Q132. K-a rays are generated when transition of an electron occurs from:

• A. K to M shell
• B. N to K shell
• C. L to K shell✓
• D. M to L shell

Explanation: K-alpha (Kα) rays are a type of X-ray that is emitted when an electron transitions from a higher energy level to a lower energy level, specifically from the L shell (n=2) to the K shell (n=1). This transition occurs when an electron fills a vacancy in the K shell, resulting in the emission of a Kα X-ray.

Q133. The decay constant of sodium (Na) is 0.0000128 /s. The half-life of sodium is:

• A. 15 hrs✓
• B. 16 hrs
• C. 900 s
• D. 3600 s

Explanation: The half-life (t1/2) of a substance is related to its decay constant (λ) by the following equation:t1/2 = ln(2) / λwhere:ln(2) = natural logarithm of 2 ≈ 0.693Given:λ = 0.0000128/sSubstituting the value, we get:t1/2 = 0.693 / 0.0000128t1/2 ≈ 54,000 sConverting seconds to hours:t1/2 ≈ 54,000 s / 3600 s/h ≈ 15 hoursHowever, this is not among the options. Let's recheck the calculation:t1/2 ≈ 0.693 / 0.0000128t1/2 ≈ 54,000 s / 10,800 s/h ≈ 5 hours

Q134. At the end of 14 min, 1/16 of a sample of radioactive Polonium remains. The corresponding half-life is:

• A. (7/8) min
• B. (8/7) min
• C. (7/4) min
• D. (7/2) min✓

Explanation: N(t) = No × (1/2)^(t/T)N(t) = remaining amount after time tNo = initial amountt = time elapsed (14 min)T = half-life (unknown)Given:N(t) = 1/16 N0 (remaining amount after 14 min)(1/16) = (1/2)^(14/T)(1/2)^4 = (1/2)^(14/T)Comparing the exponents, we get:4 = 14/TSolving for T, we get:T = 14/4T = 7/2T = 3.5 min

Q135. According to Bohr’s model of the hydrogen atom, electrons move in specific orbits around the nucleus called.

• A. Quanta
• B. Shell✓
• C. Clouds
• D. Wavelengths

Explanation: According to Bohr's model of the hydrogen atom (1913), electrons occupy specific energy levels or shells around the nucleus. These shells are labeled as K, L, M, N, etc., and correspond to specific energy levels. Electrons jump from one shell to another by emitting or absorbing energy in the form of photons

Q136. According to first law of thermodynamics, what is the relationship between the change in the internal energy of a closed system ΔU, the head added to the system (Q) and the work done by the system W.

• A. ΔU=Q+W
• B. ΔU=Q-W✓
• C. ΔU=Q*W
• D. ΔU=Q/W

Explanation: The first law of thermodynamics, also known as the law of energy conservation, states that the change in internal energy (ΔU) of a closed system is equal to the heat added to the system (Q) minus the work done by the system (W):ΔU = Q - WThis equation indicates that:- If heat is added to the system (Q > 0), the internal energy increases.- If work is done by the system (W > 0), the internal energy decreases.- If the system is adiabatic (Q = 0), the change in internal energy is equal to the negative of the work done

Q137. Angular displacement is measured in

• A. Degree
• B. Revolutions
• C. Radians
• D. All✓

Explanation: Angular displacement can be measured in:a. Degrees (°): A unit of measurement for angles, where 360° represents a full circle.b. Revolutions: A complete rotation or cycle, often used to describe rotational motion.c. Radians (rad): A unit of measurement for angles, defined as the angle subtended at the center of a circle by an arc equal in length to the radius of the circle. 2π radians represent a full circle.

Q138. Centrifugal force =

• A. mv^2/r✓
• B. m^2v/r
• C. mv/r^2
• D. mv2/r

Explanation: Centrifugal force (F_c) is an outward force that arises when an object moves in a circular path. It is given by the equation:F_c = (m × v^2) / rwhere:m = mass of the objectv = velocity of the objectr = radius of the circular path

Q139. Circular periodic waves can be generated

• A. In a ripple tank using spherical dippers✓
• B. Using electromagnetic vibrator
• C. By giving sudden up and down movement to a rope with one fixed end
• D. All of the above

Explanation: A ripple tank is a shallow glass tank filled with water where waves are generated to study their behavior. By using spherical dippers (small, rounded objects), you can create circular waves on the surface of the water. When these dippers are dipped into the water, they generate concentric, circular waves that spread outward.this is correct option

Q140. If a moving object has no force acting on it.

• A. It will decelerate and eventually stop
• B. Continue to move in a straight line at constant velocity✓
• C. It will stop immediately
• D. Its velocity will increase while moving in a straight line

Explanation: According to Newton's First Law of Motion, also known as the Law of Inertia, an object at rest will remain at rest, and an object in motion will continue to move with a constant velocity, unless acted upon by an external force. Since there is no force acting on the object, it will maintain its state of motion and continue to move in a straight line at a constant velocity.

Q141. If the acceleration of a body in one inertial frame is zero, its acceleration in any other inertial frames is

• A. Increased
• B. Zero✓
• C. Decreased
• D. Increased and then decreased

Explanation: According to the principle of relativity, if an object is at rest or moving with a constant velocity in one inertial frame, it will also be at rest or moving with a constant velocity in any other inertial frame. Inertial frames are reference frames in which an object moves with a constant velocity unless acted upon by an external force.Since acceleration is the rate of change of velocity, if an object has zero acceleration in one inertial frame, its velocity is constant. In another inertial frame, the object's velocity may be different, but its acceleration will still be zero if the velocity is constant.

Q142. If the amount of work W is required to move a charge Q from one point to another then the potential difference between the two points is given by

• A. V=W/Q✓
• B. V=Q/W
• C. Q=W/V
• D. Q=V/W

Explanation: The potential difference (V) between two points is defined as the work (W) required to move a unit charge (Q) from one point to the other. Mathematically, this is expressed as:V = W/QThis equation shows that the potential difference is directly proportional to the work done and inversely proportional to the charge

Q143. A photon while passing through a magnetic field is deflected towards:

• A. North pole
• B. Are ionized
• C. South pole
• D. None of these✓

Explanation: Option D) "None of these" is the correct optionPhotons, as electromagnetic waves, do not carry an electric charge, and they are not affected by magnetic fields. Magnetic fields only interact with charged particles, causing them to experience a magnetic force and possibly get deflected.Since photons are uncharged, they do not experience any deflection or interaction with a magnetic field. Therefore, the correct choice is "none of these" because the magnetic field does not affect photons.

Q144. In special theory of relativity, the law of conservation of energy and law of conservation of mass have been replaced with

• A. The law of conservation of mass only
• B. Law of conservation of mass-energy✓
• C. law of conservation of energy only
• D. All of the above

Explanation: In the special theory of relativity, Albert Einstein showed that mass (m) and energy (E) are equivalent and can be converted into each other, as expressed by the famous equation:E = mc^2This means that the laws of conservation of energy and conservation of mass are no longer separate, but are combined into a single law: the law of conservation of mass-energy. This law states that the total mass-energy of a closed system remains constant over time.

Q145. In three dimensional Cartesian Coordinate system (x,y,z), you have two vectors A and B. Vector A has components Ax= 4, Ay=3, and Az=2, while vector B has components Bx=1, By=5, and Bz=2. What is dot (scalar product) of vectors A and B?

• A. 23✓
• B. -23
• C. 0
• D. 19

Explanation: To find the dot product (scalar product) of vectors A and B, you multiply the corresponding components and add them together:A · B = Ax_Bx + Ay_By + Az_Bz= (4)_(1) + (3)_(5) + (2)_(2)= 4 + 15 + 4= 23So, the correct answer is b. 23.The dot product is a scalar value that represents the amount of "similarity" between the two vectors. In this case, the result is positive, indicating that the vectors have some degree of alignment.

Q146. In case of doppler effect, the apparent frequency will be _ the actual frequency when the source moves towards the stationary observer

• A. less than
• B. more that✓
• C. equal to
• D. none of these

Explanation: The Doppler effect states that when a source of waves (such as sound or light) moves towards a stationary observer, the apparent frequency of the waves increases. This is because the source is moving towards the observer, so the waves are "bunched up" and reach the observer more frequently, resulting in a higher apparent frequency.Conversely, when the source moves away from the observer, the apparent frequency decreases.So, when the source moves towards the stationary observer, the apparent frequency is more than the actual frequency.

Q147. Magnetic flux is maximum when the angle between the magnetic field and the normal to the plane of finite area is

• A. Zero degree✓
• B. 90 degree
• C. 60 degree
• D. 30 degree

Explanation: Magnetic flux (Φ) through a finite area is given by:Φ = B × A × cos(θ)where:B = magnetic field strengthA = area of the planeθ = angle between the magnetic field and the normal to the planeWhen θ = 0°, the magnetic field is parallel to the normal, and cos(0°) = 1. This means the magnetic flux is maximum, since the field lines pass through the area at a 90° angle, resulting in the maximum amount of flux.

Q148. Measure of displacement covered with passage of time is called.

• A. Acceleration
• B. speed
• C. velocity✓
• D. Deceleration

Explanation: This is the rate at which displacement changes with respect to time. It is a vector quantity, meaning it has both magnitude and direction. This is correct option

Q149. Newton's 3rd law of motion is correlated with

• A. law of conservation of energy
• B. momentum✓
• C. law of conservation of velocity
• D. All

Explanation: Newton's 3rd law of motion states: "For every action, there is an equal and opposite reaction." This means that when object A exerts a force on object B, object B exerts an equal and opposite force on object A.This law is closely related to the law of conservation of momentum, which states that the total momentum of a closed system remains constant over time. When object A exerts a force on object B, it transfers momentum to object B, and vice versa. The equal and opposite forces result in equal and opposite changes in momentum, conserving the total momentum of the system.

Q150. Ohm's law states that the current is directly proportional to _ and inversely proportional to _

• A. resistance, current
• B. resistance, voltage
• C. voltage, current
• D. voltage, resistance✓

Explanation: Ohm's law states that the current (I) flowing through a conductor is directly proportional to the voltage (V) applied across it, and inversely proportional to the resistance (R) of the conductor. Mathematically, this is expressed as:I ∝ V/RorI = V/RThis means that:- If voltage increases, current increases (direct proportionality)- If resistance increases, current decreases (inverse proportionality)

Q151. The ability to produce an electromotive force by changing the magnetic field inside a coil is used to generate.

• A. mechanical energy
• B. electricity✓
• C. electromagnetic force
• D. magnetic energy only

Explanation: The ability to produce an electromotive force (EMF) by changing the magnetic field inside a coil is the principle behind electromagnetic induction, which is used to generate electricity. This is the basis for many electric generators, including power plants, dynamos, and transformers.When the magnetic field inside a coil changes, an electric current is induced in the coil. This is known as electromagnetic induction. The changing magnetic field can be achieved by:- Moving a magnet near the coil- Rotating the coil within a magnetic field- Changing the current in a nearby coil

Q152. The absolute potential energy of a spaceship on the surface of the earth is:

• A. GmMe/Re^2
• B. GMe/Re
• C. GmMe/2Re
• D. -GMe/Re✓

Explanation: The absolute potential energy (U) of an object, such as a spaceship, on the surface of the Earth can be calculated using the formula:U = -G * (m * M_E) / r_Ewhere:- G is the gravitational constant- m is the mass of the spaceship- M_E is the mass of the Earth- r_E is the radius of the EarthThis formula represents the gravitational potential energy of the spaceship due to its position on the Earth's surface. The negative sign indicates that the potential energy is lower on the surface than at infinity

Q153. The bird perching on a high-power line does not get electroshock. This is because.

• A. The whole body of the bird sitting on the live wire is at the same potential and hence no current flows through the body✓
• B. The whole body of the bird sitting on the live wire is at zero potential and hence no current flows through the body
• C. Because the air medium between the live wire and the earth contains large numbers of charged particles
• D. Because the air medium between the live wire and the earth contains large number of electrons

Explanation: The whole body of the bird sitting on the live wire is at the same potential and hence no current flows through the body.When a bird perches on a high-power line, its entire body is at the same electric potential as the wire. Since there is no potential difference between different parts of the bird's body, no electric current flows through it. This is because electric current requires a potential difference (voltage) to drive it, and in this case, there is no voltage across the bird's body

Q154. The capacitance of capacitor depends upon

• A. area of the plates
• B. distance between the plates
• C. dielectric between them
• D. All✓

Explanation: The capacitance (C) of a capacitor depends on three main factors:1. *Area of the plates (A)*: Increasing the area of the plates increases the capacitance, as more charge can be stored.2. *Distance between the plates (d)*: Decreasing the distance between the plates increases the capacitance, as the electric field between them becomes stronger.3. *Dielectric between them (ε)*: The dielectric material between the plates affects the capacitance, as it determines the strength of the electric field and the amount of charge that can be stored.The capacitance of a capacitor is given by the formula:C = ε₀εₐA/dwhere:ε₀ = vacuum permittivityεₐ = relative permittivity of the dielectric materialA = area of the platesd = distance between the plates

Q155. The Compton's effect is the phenomenon that describes

• A. The scattering of the light by prism
• B. The bending of light when it passes from one medium to another
• C. The change in the wavelength of X-rays when they interact with matter✓
• D. The creation of interference patterns in a double-slit experiment

Explanation: The Compton effect is a phenomenon in physics where the wavelength of X-rays or gamma rays changes when they interact with matter, specifically when they scatter off electrons. This effect is named after Arthur Compton, who first observed it in 1923.When X-rays or gamma rays interact with electrons, some of their energy is transferred to the electrons, causing the wavelength of the radiation to increase (or shift towards the red end of the spectrum). This effect is a result of the conservation of energy and momentum in the interaction between the radiation and the electrons.

Q156. The current produced by a generator is called

• A. Direct current
• B. Pulsating current
• C. Alternating current✓
• D. Variable current

Explanation: A generator, also known as an alternator, produces an alternating current (AC). AC is a type of electric current that periodically reverses direction, oscillating at a specific frequency. This is in contrast to direct current (DC), which flows in one direction only.

Q157. The device used to adjust voltage levels in an electrical circuit is called

• A. Voltage regulator✓
• B. Circuit Breaker
• C. Capacitor
• D. Transformer

Explanation: A voltage regulator is an electronic device that is used to regulate and stabilize the voltage levels in an electrical circuit. Its primary function is to maintain a constant output voltage, despite changes in the input voltage or load conditions.

Q158. The distance covered by sound wave per unit time is called

• A. Speed of sound wave✓
• B. Velocity of sound wave
• C. Wavelength of sound wave
• D. Amplitude of sound wave

Explanation: The speed of a sound wave is the distance it travels per unit time, typically measured in meters per second (m/s). It is a fundamental property of sound waves and depends on the medium through which the sound is propagating, such as air, water, or solids.

Q159. The domestic electricity supply has a frequency of

• A. 150Hz
• B. 50Hz✓
• C. 100Hz
• D. 200Hz

Explanation: In most countries, the domestic electricity supply, also known as the mains electricity or grid power, has a frequency of 50Hz (50 cycles per second). This is the standard frequency for alternating current (AC) power distribution systems in many parts of the world, including Europe, Asia, and Africa.In some countries, like the United States and Canada, the domestic electricity supply has a frequency of 60Hz (60 cycles per second)

Q160. The instantaneous power supplied to a circuit is a product of the _ and _.

• A. Instantaneous current, instantaneous voltage✓
• B. Instantaneous power, instantaneous voltage
• C. instantaneous voltage, instantaneous conductance
• D. Instantaneous current, instantaneous power

Explanation: The instantaneous power (P) supplied to a circuit is the product of the instantaneous current (I) and instantaneous voltage (V):P = V x IThis is known as the power equation, and it shows that power is the product of the voltage and current at any given instant in time

Q161. The number of waves passing through a certain point in unit time is called.

• A. Wave speed
• B. Time period
• C. Wavelength of waves
• D. Frequency of waves✓

Explanation: The frequency of waves is the number of waves that pass through a certain point in a unit of time, typically measured in Hertz (Hz). It is a measure of how many waves pass through a point in one second.

Q162. The primary purpose of rectification in an electrical circuit is to

• A. Convert Direct current (DC) into Alternating current (AC)
• B. Smooth out voltage fluctuations
• C. Convert AC to DC by allowing current to flow in one direction✓
• D. Amplify electrical signals

Explanation: Rectification is the process of converting Alternating Current (AC) to Direct Current (DC) by allowing current to flow in one direction only. This is typically done using a rectifier, such as a diode or a group of diodes, which converts the AC voltage to a pulsating DC voltage.The primary purpose of rectification is to convert the AC voltage from a power source, such as a wall outlet, to a DC voltage that can be used by electronic devices, such as smartphones, laptops, and televisions.

Q163. The radial acceleration is also considered as:

• A. Angular acceleration
• B. Centripetal acceleration✓
• C. Tangential acceleration
• D. Translator acceleration

Explanation: Radial acceleration, also known as centripetal acceleration, is the acceleration of an object moving in a circular path towards the center of the circle. It is directed towards the center of the circle and is necessary to keep the object on its circular path.

Q164. The resistance of the conducting material depends upon

• A. The nature of the conductor
• B. Dimension of the conductor
• C. Physical state of the conductor
• D. All✓

Explanation: The resistance of a conducting material depends on several factors, including:a. The nature of the conductor: Different materials have different resistivities, which affect the resistance.b. Dimensions of the conductor: The length, cross-sectional area, and shape of the conductor influence the resistance.c. Physical state of the conductor: Temperature, pressure, and other physical conditions can impact the resistance.

Q165. The SI unit of capacitance is

• A. Watts
• B. Henry
• C. Farads✓
• D. Joules

Explanation: The SI unit of capacitance is the farad (F), which is defined as the capacitance of a capacitor that stores one coulomb of electric charge when a potential difference of one volt is applied across it.

Q166. The SI unit of electric potential is:

• A. Volt✓
• B. Coulomb
• C. Ampere
• D. Ohm

Explanation: The SI unit of electric potential, also known as voltage, is the volt (V). It is defined as the potential difference required to produce a current of one ampere through a resistance of one ohm.

Q167. The thermal energy required to cause a unit temperature rise is called

• A. Heat Capacity✓
• B. Heat Volume
• C. Heat Conductor
• D. Heat energy/ unit volume

Explanation: Heat capacity (C) is the amount of thermal energy required to raise the temperature of a substance by one unit (usually one degree Celsius or Kelvin). It is a measure of a substance's ability to absorb and store thermal energy. Heat capacity is typically expressed in units of energy per unit temperature, such as joules per degree Celsius (J/°C) or joules per kelvin (J/K).

Q168. The waves in which the particles of the medium vibrate about their mean position along the direction of propagation of the waves are called

• A. Longitudinal waves✓
• B. Transverse waves
• C. Mechanical waves
• D. Electromagnetic waves

Explanation: Longitudinal waves are waves in which the particles of the medium vibrate back and forth along the direction of propagation of the wave. This means that the particles compress and expand in the same direction as the wave is traveling. Examples of longitudinal waves include sound waves in a gas or liquid, and seismic P-waves in the Earth.

Q169. There are 2 pianos playing the same note, however the vibration from one piano is 223.20 Hz and that of the other is 223.50 Hz. The beat frequency between the two tones will be?

• A. 0.3 Hz✓
• B. -0.3 Hz
• C. 0 Hz
• D. 223.35 Hz

Explanation: The beat frequency is the difference between the two frequencies. To find the beat frequency, subtract the smaller frequency from the larger frequency:Beat frequency = 223.50 Hz - 223.20 Hz = 0.30 HzThis means that the two tones will produce a beat frequency of 0.3 Hz, which is the frequency at which the two tones will alternately reinforce and cancel each other.

Q170. Weber is the unit of

• A. Electric potential
• B. Electric intensity
• C. Magnetic intensity
• D. Magnetic flux✓

Explanation: The weber (Wb) is the unit of magnetic flux, which is a measure of the amount of magnetic field that passes through a given area. Magnetic flux is a measure of the strength of a magnetic field and is defined as the dot product of the magnetic field and the area vector

Q171. What happens to a football which is inflated in a warm room, is used to play outside in cold weather?

• A. It will expand due to expansion of the air molecules
• B. It will deflate due to contraction of the air molecules✓
• C. Its size will not be affected by the change in temperature
• D. It will burst.

Explanation: When the football is inflated in a warm room, the air molecules inside the ball are moving rapidly and are spaced farther apart, occupying more volume. As the ball is taken outside into cold weather, the air molecules slow down and move closer together, occupying less volume. This contraction of air molecules causes the pressure inside the ball to decrease, resulting in a deflation of the ball.

Q172. What is the rest mass of a photon?

• A. Zero✓
• B. Equal to the mass of electron
• C. Equal to the mass of proton
• D. Infinite

Explanation: Photons, being massless particles, have a rest mass of zero. According to special relativity, photons always travel at the speed of light (c) and have no rest mass. This means that a photon's energy (E) is equal to its momentum (p) multiplied by the speed of light (E = pc), and its rest mass is zero.

Q173. Which of the following best describes inertia?

• A. The force of gravity acting on an object
• B. The resistance of an object to a change in its state of motion✓
• C. The weight of an object
• D. The acceleration of an object due to applied force

Explanation: Inertia is the property of an object to resist changes in its state of motion. According to Newton's First Law of Motion, an object at rest will remain at rest, and an object in motion will continue to move with a constant velocity, unless acted upon by an external force. This means that an object will maintain its state of motion unless a force is applied to it.Inertia is a measure of an object's resistance to changes in its motion, and it is dependent on the object's mass. The more massive an object is, the more inertia it has, and the more force is required to change its state of motion.

Q174. Which of the following materials have a negative temperature coefficient?

• A. Germanium and silicon✓
• B. Germanium and iron
• C. Iron and silicon
• D. Iron and copper

Explanation: Germanium and silicon, which are semiconductors, exhibit a negative temperature coefficient of resistance. This means that their electrical resistance decreases as temperature increases.Here's why:- Germanium and silicon have a negative temperature coefficient because as temperature increases, the vibrations of the atoms (thermal energy) help to excite electrons into the conduction band, increasing conductivity and reducing resistance.- Iron (a metal) has a positive temperature coefficient, meaning its resistance increases with temperature.- Copper (a metal) also has a positive temperature coefficient, meaning its resistance increases with temperature.

Q175. Which of the following quantities is correctly matched to its unit?

• A. Electric charge: Ampere (A)
• B. Current: Volt (V)
• C. Electric power: Watt (W)✓
• D. Resistance: coulomb

Explanation: Electric power: Watt (W), which is correct. Watt is the unit of electric power, defined as the rate of energy transfer.

Q176. _ going to sleep, I like to read for half an hour.

• A. After
• B. Before✓
• C. As soon as
• D. While

Explanation: The sentence should read: "Before going to sleep, I like to read for half an hour."This indicates that reading is a habit you enjoy before falling asleep.

Q177. We are all looking forward _ the announcement of election soon.

• A. For
• B. To✓
• C. About
• D. On

Explanation: The sentence should read: "We are all looking forward to the announcement of the election soon."The phrase "looking forward to" is an idiomatic expression that means eagerly awaiting or anticipating something. In this case, it's the announcement of the election.

Q178. The dogs _ escaped.

• A. Did
• B. Has
• C. Had✓
• D. Will

Explanation: The sentence should read: "The dogs had escaped."The verb "had escaped" is in the past perfect tense, indicating that the dogs' escape occurred before another action or time in the past.

Q179. Maria _ that she could not attend classes next week.

• A. Told his professors
• B. Said her professors
• C. Told her professors✓
• D. Is telling her professors

Explanation: The sentence should read: "Maria told her professors that she could not attend classes next week."This indicates that Maria informed her professors about her inability to attend classes

Q180. _ you like a cup of coffee?

• A. May
• B. Shall
• C. Can
• D. Would✓

Explanation: "Would" (d) is the correct choice because it's used to make polite offers or invitations. It's a gentle way to ask someone if they want something.

Q181. The synonym for “promptly” is:

• A. Slovenly
• B. Instantly✓
• C. Diligently
• D. Intelligently

Explanation: "Promptly" means doing something immediately or at the expected time. "Instantly" is a synonym that also means doing something immediately or without delay.

Q182. The police _ arrested the suspect.

• A. Has
• B. Have✓
• C. Be
• D. Been

Explanation: The sentence should read: "The police have arrested the suspect."

Q183. Identify the part of the sentence that carries error:How much spoonfuls of sugar would you like in your tea?

• A. Much✓
• B. Sugar
• C. Like
• D. In

Explanation: The correct answer is (a) Much.The error is in the word "much", which is used for uncountable nouns, whereas "spoonfuls" is a countable noun. The correct word to use would be "many".The corrected sentence would be:"How many spoonfuls of sugar would you like in your tea?"

Q184. The phrase “spiffed up” stands for:

• A. Dressed up✓
• B. Cleaned up
• C. Upset
• D. Fade

Explanation: The correct answer is (a) Dressed up."Spiffed up" is an idiomatic expression that means to dress up or make something or someone look neat, tidy, and attractive. It can also mean to improve or enhance something's appearance.Example sentences:- She spiffed up for the party by wearing a beautiful dress.- The hotel room was spiffed up with fresh flowers and new linens.

Q185. Read the following passage to answer the given question:In prolonged space flight, besides the obvious hazards of meteors, rocky debris, and radiation, astronauts will have the deal with muscle atrophy brought on by weightlessness; therefore, when they return to Earth, they face a protracted period of weight training to rebuild their strength. What is the most likely meaning of the word “debris” as it is used in this passage?

• A. Fragments✓
• B. Decay
• C. Bacteria
• D. Alien life

Explanation: In the passage, "debris" refers to small, broken pieces of rock or other materials that are floating in space and could potentially collide with a spacecraft. This usage is consistent with the common meaning of "debris" as fragments or remains of something that has been broken or destroyed.In this context, "debris" is used to describe a hazard that astronauts may encounter during space flight, alongside meteors and radiation.

Q186. The money, property, etc that is used to start or operate a business is called?

• A. Cost
• B. Asset
• C. Capital Investment✓
• D. Fiscal status

Explanation: Capital refers to the money, property, or other resources used to start or operate a business. It can include funds, assets, and investments used to finance a company's operations, growth, and expansion.

Q187. The Queen of England bestowed a title upon the man who saved her life from a fatal accident. What does the underlined word mean?

• A. Conferred✓
• B. Discard
• C. Withdrawn
• D. Retailed

Explanation: "Bestowed" means to give or confer something, such as a title, honor, or gift, upon someone in a formal or official manner. In this context, the Queen of England formally gave a title to the man who saved her life as a way of recognizing and rewarding his heroic actions.

Q188. Correct the given sentence:I like cats, I hate dogs.

• A. I like cats: I hate dogs
• B. I like cats I hate dogs
• C. I like cats' I hate dogs
• D. I like cats but I hate dogs✓

Explanation: The sentence need a conjunction to connect the two contrasting clauses "I like cats" and "I hate dogs". The conjunction "but" is commonly used to express a contrast between two ideas. So, the correct sentence is:"I like cats but I hate dogs."

Q189. Add suitable conjunction in the given sentence. Your ice cream will melt, you should eat it quickly.

• A. Your ice cream will melt so you should eat it quickly✓
• B. Your ice cream will melt however you should eat it quickly
• C. Your ice cream will melt so that you should eat it quickly.
• D. Your ice cream will melt, however you should eat it quickly.

Explanation: The correct answer is (a) Your ice cream will melt, so you should eat it quickly.The conjunction "so" is used to indicate a cause-and-effect relationship between the two clauses. The first clause ("Your ice cream will melt") is the cause, and the second clause ("you should eat it quickly") is the effect or the recommended action to take.

Q190. choose the correct option

• A. These scissors are very sharp.✓
• B. This scissor is very sharp.
• C. This scissors is very sharp.
• D. These scissor are very sharp.

Explanation: The correct answer is Option A: These scissors are very sharp. In this sentence, 'scissors' is a plural noun, so the verb 'are' correctly agrees with it.Option B is incorrect because 'scissor' is not used in standard English as a singular term; 'scissors' is always plural. Option C is incorrect as it uses 'is' with a plural noun, leading to a subject-verb agreement error. Lastly, Option D incorrectly uses 'scissor' in a plural context, which is also not standard usage.

Q191. Choose the sentence with correct word order.

• A. Sue took from the window the cover.
• B. Sue cover from the window took the cover.
• C. Sue took the cover from the window.✓
• D. Sue the cover took from the window.

Explanation: The correct answer is (c) Sue took the cover from the window.This sentence has the correct word order:- Subject (Sue)- Verb (took)- Object (the cover)- Prepositional phrase (from the window)

Q192. "To cut off the head"This idiom means:

• A. Defrock
• B. Decapitate✓
• C. Impaled
• D. Urbanite

Explanation: The idiom "to cut off the head" means to remove or get rid of the leader, chief, or most important person in a group, organization, or system. It can also be used literally to mean beheading or decapitating someone. However, in modern usage, it's often used figuratively to mean removing someone from a position of power or authority.

Q193. Choose the correct option.We must _ the tickets for the movie in advance.

• A. Remove
• B. Take
• C. Draw
• D. Buy✓

Explanation: The sentence should read: "We must buy the tickets for the movie in advance." "Buy" is the correct verb to use in this context, as it means to purchase or acquire something (in this case, tickets).

Q194. Read the paragraph carefully and answer the question given. “Over the past century the businessman has helped build civilization's great cities, provided people with luxuries and lifted his fellow citizens to a certain standard of living. Further seeding the industrial revolution around the world.

• A. Is accountable to the society
• B. Provides seeds to agricultural sector
• C. Is the beneficiary of the industrial revolution
• D. Has contributed to the growth of civilisation✓

Explanation: The paragraph highlights the positive impact of the businessman on society, stating that they have helped build great cities, provided luxuries, lifted people's standard of living, and furthered the industrial revolution. This suggests that the businessman has made significant contributions to the growth and development of civilization.

Q195. Some months have 31 days, how many have 28?

• A. One month and that is February
• B. February, every 4 years
• C. All months have 28 days✓
• D. None

Explanation: This question requires logical deduction. While some months have 31 days, and February typically has 28 or 29 days, the question asks how many months have at least 28 days. The correct answer is all 12 months, as every month has at least 28 days.

Q196. Read the following and choose the correct answer. Mice are to cats as goats are to,

• A. Snakes
• B. Hippos
• C. Horses
• D. Lions✓

Explanation: The analogy is based on predator-prey relationships. Mice are prey for cats, so the analogy is looking for an animal that is a predator of goats. Lions are predators that feed on goats, making them the correct answer.

Q197. Read the following statements and identify the best cause and effect relation. (I) For the past four years, the district’s literacy rate has been rising. (II) The district administration organise a thorough training program for the volunteers working on the literacy campaign

• A. II is the cause of I is its effect✓
• B. I is the cause and II is its effect
• C. I and II are effects of some common cause
• D. I and II are both effects of independent causes

Explanation: The correct answer is (a) II is the cause and I is its effect.Explanation:The training program for volunteers (II) is likely to improve their effectiveness in teaching literacy skills, leading to an increase in the district's literacy rate (I). This suggests that the training program is the cause, and the rising literacy rate is the effect.

Q198. Observe and the pattern and select the next term in the sequence:P5QR, P4QS, P3QT, _, P1QV

• A. P2QU✓
• B. PQ3U2
• C. P2QUY
• D. PQ3U

Explanation: The correct answer is (a) P2QU.Explanation:The pattern in the sequence is a decrease in the number preceding the letter "P" by 1 each time, and an increment in the letter following "Q" by 1 position in the alphabet.Here's the breakdown:- P5QR -> P4QS (decrease 5 to 4, increment R to S)- P4QS -> P3QT (decrease 4 to 3, increment S to T)- P3QT -> P2QU (decrease 3 to 2, increment T to U)

Q199. Statement: Due to increasing pollution, the government bans to use of all single-use plastic products from next years, “Courses of Action:An awareness campaign is introduced by the government to encourage people to use eco-friendly products.Subsidies to be provided to companies that manufacture eco-friendly products.

• A. Only I follows
• B. Only II follows
• C. Neither I and II follow
• D. Both I and II follow✓

Explanation: The government's decision to ban single-use plastic products is a policy change aimed at reducing pollution. To support this change, the government can take two courses of action:I. Introducing an awareness campaign to educate people about the importance of using eco-friendly products. This will help change consumer behavior and increase demand for eco-friendly alternatives.II. Providing subsidies to companies that manufacture eco-friendly products. This will incentivize businesses to produce more eco-friendly products, making them more widely available and affordable for consumers.Both courses of action are logical consequences of the government's decision to ban single-use plastic products. They work together to create a supportive environment for the transition to eco-friendly products.

Q200. What is primary function of Grignard reagent in organic reactions?

• A. To act as strong acid
• B. To act as nucleophile and add to carbonyl compounds✓
• C. To act as electrophile
• D. To catalyze hydrogenation reaction

Explanation: Grignard reagents are highly reactive nucleophiles that add to carbonyl compounds such as aldehydes and ketones to form addition products.